63229-68-5Relevant academic research and scientific papers
Oxazolidinones and 2,5-Dihydrofurans via Zinc-Catalyzed Regioselective Allenylation Reactions of l -α-Amino Aldehydes
Zamani, Farzad,Pyne, Stephen G.,Hyland, Christopher J. T.
, p. 6819 - 6830 (2017/07/17)
The simultaneous control of diastereoselectivity and regioselectivity in Zn-catalyzed allenylation reactions of N-protected l-α-amino aldehydes is reported. A reversal in diastereoselectivity could be realized by variation of the α-amino aldehyde protecti
Preparation of the optically pure N-methyl amino ester method and product
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Paragraph 0053-0054, (2017/04/13)
The invention belongs to the field of organic synthesis of amino acids and discloses a method for preparing optically pure N-methyl amino-acid ester. The method comprises the following steps of carrying out esterification reaction on amino acid as a starting raw material and aldehyde to form an imine intermediate, carrying out reductive amination in the presence of palladium carbon, and carrying out hydrogenation and debenzylation to finally synthesize optically pure N-methyl amino-acid ester. The method has the advantages of simplicity in method, mild reaction conditions and good adaptability and side chains of D-type or L-type amino acid do not need to be protected.
Biology-oriented combined solid-and solution- phase synthesis of a macroline-like compound collection
Wilk, Wolfram,Noeren-Mueller, Andrea,Kaiser, Markus,Waldmann, Herbert
scheme or table, p. 11976 - 11984 (2010/05/17)
Macrolines constitute a class of natural products that has more than 100 members and displays diverse biological activities. These compounds feature a cycloocta[b]indole scaffold that represents an interesting target structure for biology-oriented synthesis (BIOS). We have presented a solid-phase synthesis of isomerically pure cycloocta[b]indoles by employing the Pictet-Spengler reaction and the Dieckmann cyclization as key steps. The scope of this reaction sequence was investigated in more detail by using various additional diversification procedures, such as Pd-catalyzed Sonogashira or Suzuki couplings on a solid phase, thus allowing, for example, the generation of 10-substituted cycloocta-[b]indole derivatives. Finally, solution-phase decoration of the cycloocta[b]indole skeleton by reduction and saponification was evaluated, thereby further extending the scope of the solid-phase synthesis.
Facile synthesis of highly functionalized N-methyl amino acid esters without side-chain protection
White, Kimberly N.,Konopelski, Joseph P.
, p. 4111 - 4112 (2007/10/03)
(Chemical Equation Presented) The facile, two-pot synthesis of N-methyl amino acid esters by way of reductive amination is presented. Side chain protection schemes are not required, the starting materials are all commercially available, and the synthetic
General approach for the synthesis of sarpagine indole alkaloids. Enantiospecific total synthesis of (+)-vellosimine, (+)-normacusine B, (-)-alkaloid Q3, (-)-panarine, (+)-Na-methylvellosimine, and (+)-Na-methyl-16-epipericyclivine
Yu, Jianming,Wang, Tao,Liu, Xiaoxiang,Deschamps, Jeffrey,Flippen-Anderson, Judith,Liao, Xuebin,Cook, James M.
, p. 7565 - 7581 (2007/10/03)
The first total synthesis of (+)-Na-methyl-16-epipericyclivine (9) was completed [from D-(+)-tryptophan methyl ester] in an overall yield of 42% (eight reaction vessels). The optical rotation [[α]D +22.8 (c 0.50, CHCl3)] obtained on this material confirmed that the reported optical rotation [[α]D 0 (c 0.50, CHCl 3)]47 was biogenetically unreasonable. The total syntheses of (+)-vellosimine, (+)-normacusine B, (-)-alkaloid Q3, (-)-panarine, and (+)-Na-methylvellosimine are also described. Moreover, a mixed sample (1:1) of synthetic (-)-panarine and natural (-)-panarine yielded only one set of signals in the 13C NMR; this indicated that the two compounds are identical and further confirmed the correct configuration of (+)-vellosimine, (+)-normacusine B, and (-)-alkaloid Q3. In this approach, the key templates, (-)-Na-H,N b-benzyltetracyclic ketone 15a and (-)-Na-methyl,N b-benzyltetracyclic ketone 43 were synthesized on multihundred gram scale by the asymmetric Pictet-Spengler reaction and a stereocontrolled Dieckmann cyclization via improved sequences. An intramolecular palladium (enolate-mediated) coupling reaction was employed to introduce the C(19)-C(20) E-ethylidene function in the sarpagine alkaloids for the first time in stereospecific fashion.
Sodium borohydride: A versatile reagent in the reductive N-monoalkylation of α-amino acids and α-amino methyl esters
Verardo, Giancarlo,Geatti, Paola,Pol, Elena,Giumanini, Angelo G.
, p. 779 - 788 (2007/10/03)
α-Amino acids and α-amino methyl esters are easily converted to their N-monoalkyl derivatives by a reductive condensation reaction using several carbonyl compounds in the presence of sodium borohydride. This reducing agent has shown a wide versatility with minor but essential procedural variations. The reaction allows the α-monodeuterium labeling of the new N-substituent by use of sodium borodeuteride.
Synthesis and evaluation of tryprostatin B and demethoxyfumitremorgin C analogues
Wang, Haishan,Usui, Takeo,Osada, Hiroyuki,Ganesan
, p. 1577 - 1585 (2007/10/03)
Tryprostatin B and demethoxyfumitremorgin C are fungal inhibitors of mammalian cell cycle progression at the G2/M transition. N-Alkyl derivatives of the L-Trp-L-Pro diketopiperazine were prepared as analogues of tryprostatin B, and two of these
Enantiospecific total synthesis of the enantiomer of the indole alkaloid affinisine
Liu,Wang,Xu,Ma,Cook
, p. 6299 - 6303 (2007/10/03)
The enantiomer of affinisine has been synthesized (from L-tryptophan) with 100% diastereoselectivity via the asymmetric Pictet-Spengler reaction coupled with a Pd°(enolate mediated) coupling process. This enantiomer has also been converted into a key inte
Pictet-Spengler/palladium catalyzed allenylation and carbonylation processes
Grigg,MacLachlan,MacPherson,Sridharan,Suganthan,Thornton-Pett,Zhang
, p. 6585 - 6594 (2007/10/03)
The tactical combination of the Pictet-Spengler reaction with Pd catalyzed reactions with allene and with carbon monoxide provides rapid access to a range of tetrahydro-β-carboline and tetrahydroisoquinoline derivatives via intramolecular trapping of inte
Enantiospecific Total Synthesis of the Sarpagine Related Indole Alkaloids Talpinine and Talcarpine as Well as the Improved Total Synthesis of Alstonerine and Anhydromacrosalhine-methine via the Asymmetric Pictet-Spengler Reaction
Yu, Peng,Wang, Tao,Li, Jin,Cook, James M.
, p. 3173 - 3191 (2007/10/03)
The enantiospecific total synthesis of talpinine 1 and talcarpine 2 has been accomplished from D-(+)-tryptophan in 13 steps (11 reaction vessels) in 10% and 9.5% overall yields, respectively. Moreover, this synthetic approach has been employed for the improved synthesis of alstonerine 3 and anhydromacrosalhine-methine 4 in 12% and 14% overall yield, respectively. A convenient synthetic route for the enantiospecific, stereospecific preparation of the key intermediate (-)-Na-H, Nb-benzyl tetracyclic ketone 15a via the asymmetric Pictet-Spengler reaction on a multihundredgram scale has been developed. A diastereocontrolled (>30:1) anionic oxy-Cope rearrangement and the intramolecular rearrangement to form ring-E and an Nb-benzyl/Nb-methyl transfer reaction also served as key steps. This general approach can now be utilized for the synthesis of macroline/ sarpagine related indole alkaloids and their antipodes for biological screening.
